L-Valine, N-[(1,1-dimethylethoxy)carbonyl]-, (2R,3R,5R)-2-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-4,4-difluorotetrahydro-5-[2-oxo-4-[(1-oxo-2-propylpentyl)amino]-1(2H)-pyrimidinyl]-3-furanyl ester

L-Valine, 3′-ester with 2′-deoxy-2′,2′-difluoro-N-(1-oxo-2-propylpentyl)cytidine